From 8:30 to 6:30, there are 10 hours. This is calculated by counting the full hours from 8:30 to 6:30, which includes 8:30 to 9:30, 9:30 to 10:30, and so on, until 5:30 to 6:30.
8.5 hours
7 hours
7.5 hours
6 hours.
Three hours
3 hours.
8 hours 15mins.
7.5 hours
4
4.5
3½
8